Louvered damper



FIGI.

mvzmon: EINAR SETH ATTVS,

United States Patent Oflice LUUVERED DAMPER Einar Seth, Jonlroping,Sweden, assignor to Alrtiebolaget Svenska Flaktfabriiken, Stockholm,Sweden Filed May is, was, Ser. No. 456,677 Claims priority, applicationSweden, June 5, 1964,

2 Claims. (Cl. 49--92) ABSTRACT OF THE DISCLOSURE A louvered damper forcontrolling gaseous flow having a plurality of parallel louver bladesmounted within a rectangular frame by a central shaft. On one side ofthe shaft, each blade has a rigid blade profile; and on the other sideof the shaft, each blade has a resilient blade profile. An adjustingmechanism is provided to actuate the blades between an open positionthrough a closed position to a closed limit position. In the closedlimit position, the resilient profile of each blade is deformed toconform to the contour of the rigid profile of an adjoining blade toform a tight seal along the marginal overlap between the blades to cutoff the gaseous flow.

The present invention relates to an improvement in louvered dampersconsisting of a rectangular frame and a number of damper blades arrangedin the frame, so that in closed position the blades somewhat overlapeach other, each of said damper blades being provided with a centralshaft journalled in the side elements of the frame and an adjustingmechanism actuating the damper blades.

In prior dampers of the above-mentioned kind it has been diflicult toget an effective cut-off of the passing air flow because of thedifficulties in making the damper blades and the adjusting mechanismwith such precision that all the damper blades in closed positioncontact each other in sealing engagement.

The present invention, which intends to eliminate said drawbacks withsimple means, is characterized in that each damper blade on one side ofthe shaft has a rigid blade profile and on the opposite side a resilientblade profile and that the adjusting mechanism is made to turn thedamper shafts somewhat beyond the normal closing position to a closedlimit position in which the rigid blade profile deforms the adjacentoverlapping resilient blade profile and effects a tight seal along themarginal overlap.

The invention will now be more fully described with reference to theaccompanying drawing, wherein FIG. 1 shows in perspective a louvershutter in accordance with the invention with a partly cut-away frameand with the appurtenant adjusting mechanism,

FIG. 2 is a sectional view which shows the louver shutter in openposition, and

FIG 3 is a sectional view which shows the louver shutter in closedposition.

In the drawing, 1 indicates a louver shutter, consisting 3,377,745Patented Apr. 16, 1968 damper blades from open to closed and from closedto open positions respectively. The lever 5b is attached to the shaft 4and transfers the longitudinal motion of the bar 5a to a rotatingmotion, illustrated in FIG. 2 and FIG. 3 with broken-line arcs. Each oneof the damper blades has a rigid blade profile 3a on one side of theshaft and on the opposite side a resilient blade profile 3b. To obtainwith a large marginal sealing engagement between the separate damperblades and between the uppermost blade and the flange 7, the adjustingmechanism is, in accordance with the invention, made to turn the dampershafts somewhat beyond the normal closing position to a closed limitposition. This is especially shown in FIG. 3, which shows that the rigidprofile of one blade is positioned to deform or flex the resilientprofile of the adjacent overlapping blade.

The invention may also be made different from what the drawing showswithout going beyond the scope of the invention.

What I claim is:

1. A louvered damper for controlling a gaseous flow comprising a framehaving side elements, a plurality of louver blades each having a shaftjournalled in the side elements of said frame for mounting said bladesin said frame, and an adjusting mechanism to actuate said blades betweenan open position affording flow therethrough and a closed positionwherein. said blades are in marginal overlapping relation, theimprovement wherein each blade comprises a resilient blade profile onone side of said shaft and a rigid blade profile on the opposite side ofsaid shaft and connecting means interconnecting said blades with saidadjusting mechanism operable to displace said blades beyond said closedposition to a closed limit position wherein the rigid blade profile ofone blade engages against the resilient blade profile of the adjacentoverlapping blade to deform the same to effect a tight seal along themarginal overlap.

2. A louvered damper according to claim 1, wherein said frame isrectangular and includes a flange adapted to overlap the end blade andflex the resilient profile thereof when in said closed position.

References Cited UNITED STATES PATENTS 93,996 8/ 1869 Jenkins 49-922,887,034 5/1959 Gorth 49---92 X 3,204,548 9/1965 McCabe 49-91 X DAVIDJ. WILLIAMOWSKY, Primary Examiner.

EARL I. WITMER, HARRISON R. MOSELEY,

Examiners.

PHILLIP C. KANNAN, Assistant Examiner.

